1. determine which shell software you're using

$ ps $$

2. change your shell software ( bash, zsh, csh, ... )

$ bash

3. print the bash version

$ bash --version

4. print the directory location of bash

$ which bash

5. print the current user name

$ whoami

6. print the current computer name

$ hostname

7. determine if a command or token is recognized by the shell

$ type [token]

8. read all tokens from stdin and prints them to stdout

$ echo

9. suppress the automatic new line with echo command

$ echo -n

10. print the current working directory

$ pwd

11. print the contents of the current directory

$ ls

12. print the contents of a relative path within the current directory

$ ls [relative path]

13. return to the parent directory

$ cd ..

14. return to the previous directory

$ cd -

15. return to current user's home screen

$ cd

or

$ cd ~